Air-pump



No MODEL.

uy l

G. W. KELLOGG.

AIR PUMP.

PATBNTBD JAN. 5, 1904.

.APPLIGATIO FILED DBO.17,.1902.

3h00/wim Q/l//Ye Zlogg UNITED STATES Patented January 5, 1904.

PATENT OFFICE.

AIR-PUMP.

:SPECIFICATION forming part of Letters Patent No. 748,617, dated January 5, 1904. Application filed December 17I 1902. Serial No. 135,591. (No model.)

To all whom it may concern,.-

Be it known that I, GEORGE W. KELLOGG, a resident of Winsted, in the county of Litchfield and State of Connecticut, have invented certain new and useful Improvements in Air- Pumps; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it pertains to make and use the same.

Theinvention relates to air-pumps, and has for its object to simplify their construction and increase their eliiciency.

The invention consists in the construction hereinafter described and pointed out.

Figure 1 is a vertical central section. Fig. 2 is a Vertical section of a detail.

Numeral l denotes abase having a treadle or step 2 for the same whereby the base and the pump can be held by the foot or otherwise on the ground or on any suitable support. The step is pivoted to the base to permit its being folded against the side of: the pump, and it preferably comprises two members 3, each pivoted to the base and 'joined by a transverse member 4, curved to fit the pump, as indicated by broken lines in Fig. 1.

5 denotes a cylinderitted ina seat 6 in the base. 7 indicates a smaller cylinder similarly fixed in the base.

8 and 9 indicate the pistons, and 10 and 1l the piston-rods, of the respective cylinders. The rods are provided with racks 12, meshing with a gear-Wheel13. A handle for actuating piston 8 by means of its r'od 10 is denoted by 14.

l5 denotes posts or supports having bearings 17 for the axis of gear 13. These posts may be iXed on the top of the cylinders by any convenient means.

16 indicates a plate on which the posts may be IiXed. Said plate may be secured to a band 18, xed on the cylinders by set-screw 19 or by other means.

The plate 16 is slotted to receive the piston-rods to permit the opposite reciprocation of said rods, which are thus guided by the plate or cap 16.

2O denotes a port in the base, and 21 a check-valve closed when the large piston 8 ascends or isretracted and opened by the forward or downward movement of said piston.

The base has in the present instance an extension 1X, that supports the small cylinder 7. A port 22, formed in a coupling-thimble or other connection 23, communicates with the Valve-chamber 24 and also with port 20 when the check-Valve is not closed. Rings 26 are provided on the nozzle or exit-pipe 27 to securely hold a iieXble delivery-pipe. In some cases a thim ble or part 23 will extend through the boss 28 of the nozzle 27 and will have a transverse port 30, communicating with the valve-chamber. This permits the nozzle or plug 27 to be first screwed to the base, whereupon the thimble or part 23X can be screwed through its boss 28 into the extension 1 of the base. A double connection of the nozzle or plug 27 with the base and the base extension situated under the extension provides a very strong and well-protected connection.

In operation, the pump being placed on end and held by the foot bearingon the step 2, and thus securely held, the pistons are oppositely reciprocated by the handle and the rack-a'nd-gear connection. the larger piston drives air by the check-valve into and through the delivery-nozzle and also into the smaller cylinder and under its ascending piston, the ports being suitably proportioned, as approximately indicated in the drawings. Upon reversalof the movement the check-valve is closed, the air compressed in the smaller cylinder by the previous movement is delivered under added compression through the nozzle by the descending small piston, and air is admitted tothe large cylinder about its flexible packing 3l.

Having described my invention, what I claim as new, and desire to secure by Letters Patent, is-

1. In a pump, the combination of two cylinders of differing capacities, rack-pistons for said cylinders, an actuating-handle on one of said pistons, a pinion intermediate the piston-racks and meshing therewith, a delivery-conduit, an open conduit by which the smaller cylinder communicates freely with the delivery-conduit, a conduit by which the larger cylinder may communicate with each of the other conduits, and a check-valve to prevent return to the larger cylinder.

2. In a pump, the combination of two cylinders of diering capacities, pistons for said The descent of cylinders, means for actuating the pistons in opposite directions, a delivery-conduit common to the cylinders and conduits whereby each cylinder communicates with the delivery-conduit, that of the larger cylinder being provided with a check-valve to prevent entrance thereto and that of the smaller being always open.

3. In a pump, the combination of two cylinders of differing capacities, pistons for said cylinders, means for actuating the pistons in opposite directions, a delivery-conduit common to the cylinders and conduits whereby each cylinder communicates with the delivery-conduit, that of the larger cylinder being provided with a check-valve to prevent entrance thereto and that of the smaller being always open, the common delivery-conduit having a capacity less than that of the conduit by which it communicates with the smaller Cylinder.

A4c. In a pump, a cylinder-supporting base having an extension, a plurality of cylinders one carried by said extension and each having a piston and van exit-conduit communieating with a delivery-conduit, said delivery-conduit being situated immediately under said extension, whereby the cylinders may cooperate and whereby the connections are protected.

In testimony whereof I have signed this specification in the presence of two subscribing witnesses.

GEORGE W. KELLOGG.

Witnesses:

F. M. THURsToN, WILLIAM H. PHELPS. 

